Revolving drum document transport

ABSTRACT

A ROTARY DRUM DOCUMENT TRANSPORT COMPRISING A HOLLOW CYLINDRICAL ROTATING DRUM, A DOCUMENT CORNERING STATION, AND A DOCUMENT DIVERTER. THE DOCUMENT IS CORNER AND INSERTED ON THE INTERIOR OF THE DRUM AND CARRIED THEREON BY CENTRIFUGAL FORCE. THE DOCUMENT DIVERTER STRIPS THE DOCUMENT FROM THE DRUM INTERIOR AND DIRECTS IT TO A RECEIVER FOR STACKING.

eeeeeeeeeeee t 1 BY mmwzzw ATTORNEY March 2, 1971 A. L. HIATT REvoLvING DRUM DOCUMENT TRANSPORT 5 Sheets-Sheet 2 Filed Sept. 24, 1969 FIG. 2I

FIG, 3

March 2, 41971 A. L. HATT 3,5671212 REVOLVING DRUM DOCUMENT' TRANSPORT Filed Sent. 24, 1969 3 Sheets-Shee't 5 United States Patent O 3,567,212 REVOLVING DRUM DOCUMENT TRANSPORT Albert L. Hiatt, Rochester, Minn., assignor to International Business Machines Corporation, Armonk, N.Y. Filed Sept. 24, 1969, Ser. No. 860,529 Int. Cl. B65h 29/58 U.S. CI. 271-51 8 Claims ABSTRACT OF THE DISCLOSURE FIELD OF THE INVENTION This invention relates to rotary conveyors for sheet feeding and more specifically to sheet feeding transports wherein the sheet is transported in the arc of a circle during a portion of its movement.

PRIOR ART The prior art teaches the use of a rotary drum for transporting documents. Most of this prior art shows the use of the drum to carry the document on its exterior periphery. This requires some sort of holding means to overcome the centrifugal force generated by the rotation of the sheet material or document.

In an effort to overcome the complexity of these holding means (Controllers, bands, belts, o-r other apparatus) that combat the centrifugal force, an efort has been made in the art to use the interior periphery of a hollow cylindrical drum to carry sheet material or documents.

The prior art teaches the transporting of sheet material on the interior periphery of a hollow cylindrical rotating drum. Here the use of the centrifugal force to hold the document on the drum surface is useful rather than detrimental. By the use of this naturally occurring force, the holding means necessary on the external periphery of a drum are eliminated and the device becomes simpler. However, when the document is moved to the interior of the drum and carried thereon, other problems present themselves.

One problem which, heretofore, precluded efficient use of the interior of revolving drum transports, was feeding into and removal of the document from the interior of the cylinder. Prior art drums had to be stopped and loaded and restraining devices used to hold the document during acceleration. Thus, automatic and continuous Operations Were precluded.

Other problems to date have prevented the eflicient use of the interior surface of the drum as a document transort.

p One of these problems is the plaeing of the document on the interior surface of the drum such that it is properly aligned and properly positioned so that any data carried on the document may be read by the appropriate type of sensing apparatus. The prior art teaches the type of transport where a document or documents are manually placed on the interior surface of the drum while the drum is at rest. Then the drum is accelerated to its Operating speed and the centrifugal force then holds the document in its proper position.

Another example of the prior art teaches the clamping or holding of the document by a retainer on the interior surface of the drum.

3,567,212 Patented Mar. 2, 1971 Accurate placement and alignment of the document on the drum surface has been such a problem that it has prevented the use of interior drum surface transports where serial feeding is required. In the prior art, the drum had to be stopped in order to place the document accurately enough for it to be properly read or scanned. This precluded large throughputs of documents.

Another problem encountered which prevented the use of interior surface drum transports Was that of an air cushion formed between the document and the drum surface which allowed the document to flutter or skew during the insertion. The air cushion would allow the document even When manually placed on the drum surface to move and flutter during the acceleration of the drum to Operating speeds. This is the reason why some sort of clamping or retaining member was required on prior art devices. Clamps and retainers are not acceptable where the sensing apparatus must fioat in close proximity to the card surface such as the close clearance required in reading magnetic cards. The use of retainers or clamps interferes with such readings to such an extent that it is no longer useful. To overcome this problem clamps and other obstructions must be eliminated.

It is therefore a primary object of this invention to provide automatic and continuous serial feeding and removal of documents from the interior surface of a rotating hollow cylindrical drum transport.

It is another object of this invention to accurately position documents fed onto the surface of the drum transport such that acceptable reading and Scanning may be accomplished.

It is a further object of this invention to provide a reading cycle of variable duration in a document reader with respect to each document.

It is a further object of this invention to place the document on the interior surface of the hollow rotating drum transport in such a manner that the document cannot skew or flutter during insertion or revolution.

It is a still further object of this invention to transport a document on the interior surface of a hollow rotating cylindrical drum without the use of any retainer clamping or holding device.

It is a still further object of this invention to eliminate flutter of the document during its transportation on the interior surface of a hollow cylindrical drum transport.

It is an additional object of this invention to remove any air cushion between the card and drum surface during insertion thereby elminating skewing and flutter of the card.

Other objects will become apparent to one skilled in the art from the detailed explanation to follow.

SUMMARY OF THE INVENTION The primary object of the invention is accomplished by inserting a card or document onto the interior surface of a hollow rotating cylindrical drum by a cornering station and feed rollers that present the document to the drum surface in synchronizaed movement with the drum and removing a document by diverting the document from its cylindrical path as it contacts a diverter blade, and guiding it in a desired path utilizing the cards momentum to propel the card.

The diverter blade may be selectively activated at different times during the read cycle thereby controlling the read cycle duration as required.

The objects of this invention are achieved by plaeing a document on the interior of a constantly rotating cylindrical drum in such a manner that the document is under a physical control or restraint during a major portion of its insertion phase and that the document is progressively placed in contact with the surface of the drum thereby removing any air cushion which may cause misalignment or skewing. Also, the objects of the invention are accomplished by the use of the centrifugal force naturally created to hold that portion of the document in contact with the drum. This allows the centrifugal force to urge the remaining portion of the document into contact with the drum.

The elimination of clamping, hold down, or restraining devices is accomplished by the utilization of centrifugal force and the accurate placement of the document on the interior surface of the hollow cylindrical rotating drum.

In the drawings:

FIG. 1 illustrates the revolving drum transport along with its insertion feed and diverter guide.

FIG. 2 is a front view of the revolving drum transport.

FIG. 3 is a sectional view taken along line 3-3 of FIG. 2, showing the hinged diverter plate with projections and the interior of the drum.

FIG. 4a illustrates the document diverter plate out of its operative position.

FIG. 4b illustrates the document diverter plate in the operative position and stripping the document from the interior of the drum.

FIG. 5 illustrates schematically the drum transport combined with a document feed hopper and a document receiver and stacker.

DESCRIPTION OF THE INVENTION In order to transport a document, a revolving drum transport is provided and illustrated in FIG. 1. It is comprised of several Components including a revolving, hollow, cylindrical drum 10. To place the card into the revolving drum, an insertion feed and cornering mechanism generally illustrated at 12 is supplied. A document diverter 14, and a document guide 16 is likewise provided for removing the document at the completion of its reading cycle. Another Component assocated with the transport is a driver 17 for the drum. Any well known power source such as an electric motor, or other rotary drive means would be acceptable, so long as they meet the power requirements for rotating the drum.

The revolving drum is cylindrical in shape and constructed of a material which will withstand substantial centrifugal force. The drum 10 is connected to the drive means 17. To place the document on the drum interior, the invention includes an insertion and cornering mechanism 12 which comprises a guide surface 20, drive rollers 22, and pinch rollers 24 (see FIG. 2). The guide surface extends into the hollow region of the revolving drum 10 and the document comes to rest against the document arrester 26, the edge in contact with the card stop is properly aligned for feeding onto the interior surface of the drum 10.

The term cornering as used in the specification and claims means that a document is fed into the cornering station and brought to rest and moved in the same plane but in a direction perpendicular to the initial feed direction.

To corner the card and propel it toward the drum surface, drive rollers 22 and pinch rollers 24 are provided.

In FIG. 2, drive rollers 22 are supported in contact with the interior surface of the drum 10 to create a frictional contact 32 between the drive rollers and the drum. As the drum revolves, this frictional contact at 32 then rotates the drive rollers 22. The drive rollers 2 are supported slightly above the document or card having been stopped by the card stop 26.

The guide rollers are fixedly mounted on a rotatable axle to provide an equal rotation of both rolls 22. This equal rotation eliminates skewing of the card 25 during the portion of the insertion phase when the card is constrained to movement in one plane by contact with the pinch rollers 24 and feed rollers 22. Beneath the guide surface 20 are displaceably mounted pinch rollers 24. The pinch rollers 24 are movable by any Well k nown actuating means 34 (FIG. 1) in a direction such that the document or card 25 is caught between the rotating drive rollers 22 and the pinch rollers 24. It is understood that any well known electromagnetic or mechanical means could be employed to move the pinch rollers.

To remove the card from the drum surface, a diverter plate With fingers and channels in the drum interior are provided.

Referring to FIGS. 4a and 4b, the revolving drum 10 has formed into its interior cylindrical surface a plurality of channels 36. These channels allow the projecting fingers 38 of the diverter plate 14 to extend through and beyond the cylinder rotation described by the traveling card 25. The diverter plate 14 is hinged by a hinge pin 42 so that the diverter plate may be pivoted away from the interior surface of the drum 10 and thereby allow a card being revolved on the inside of the drum to be carried past the diverter plate 14 as seen in FIG. 4a, and thereby make one or more complete additional revolutions before being removed from the interior of the drum.

To control the diverter plate 14, a rapidly reacting mechanism such as an electromagnet 44 is provided. This serves to attract a tab 46 projecting from the diverter plate 14 and thereby pull the diverter plate 14 around its hinge pin 42. Thus its fingers 38 extend into the channels 36 of the drum.

Spaced apart from the other mechanisms but located at any other desirable location around the interior periphery of the drum 10 is the document read head 48 as seen in FIG. 1. This read head may be a magnetic transducer, an optical sensing read head or other type of document read head as desired. This read head is located such that the card or document 25 being transported by the drum 10 may pass between it and the interior surface of the drum 10.

A document sensing means 54 may be postioned at a point adjacent to the interior surface of the drum 10 to sense the presence or absence of a document on the drum surface. The document sensing means is illustrated in FIG. 2, but is omitted from FIG. 1 for clarity. One skilled in the art will recognize that the read head could also be used for this sensing function. The sensing output may be utilized for any of several purposes. Illustrative of such usage would be: Operation of the document diverter, deactivation of the feed mechanism, indexing the read head if the read head is of the type that requires indexing for subsequent reading passes, switching between read heads if more than one is used. Other possible uses of the card sensor will become apparent to one skilled in the art.

The insertion cornering mechanism may be combined with any conventional document feeder which imparts a velocity to the document and allows the document to move toward the rear portion of the drum and come to rest against the card stop 26. Such a card feeding mechanism is illustrated in FIG. 4 of U.S. Pat. 3,062,532 issued to Matthew J. Galatha and assigned to International Business Machines Corporation.

Likewise the document diverter guide may be combined with any pack receiving mechanism which will accommodate and arrest the documents coming from the guide and retain them in an orderly manner. Such a receiver is illustrated in U.S. Pat. 3,386,731 issued to Paul R. Brinson and assigned to International Business Machines Corporation.

The above two combinations are not disclosed in detail since clarity is served by omitting them, and they are incorporated by reference. FIG. 5 shows the arrangements of the feeder 56 and receiver 58 schematically.

The shape of the document diverter guide 16 can be characterized as a helical convolution wherein a ribbon of material is bent such that a line midpoint between the two lateral edges passes from a plane into a helical coil. The coil is then terminated prior to the completion of one-half of one helical coil, and the document diverter plate is either formed into the end of the coil or is pivotally supported thereon by a hinge connection.

OPERATION OF THE INVENTION Cards are fed individually along the card feed guide surface 20 until they are arrested and aligned by the card stop 26. At that time, an electrical impulse from some control device (not shown) activates the pinch roll actuator 34 thereby forcing the pinch rolls 24 into contact with the underside of the document in the cornering station shown generally at 12. As the pinch rolls 24 contact the underside of the card 25, the card is lifted and makes contact with the revolving drive rollers 22. The drive rollers have derived their rotation from the frictional contact .32 with the interior surface of the drum and hence, have the same tangential velocity as the interior of the drum 10. The card 25 is thus accelerated toward the interior surface of the drum 10 and is momentarily trapped between the interior of the drum 10 and the drive rolls 22. The card 25 is thereby positioned on the interior surface of the drum 10. The card is constrained by the feed rollers 22 and pinch rollers 24 as the card4 begins to conform to the interior of the drum 10, the leading portion of the card 25 comes under the infiuence of centrifugal force. When sufficient card is in contact with the drum to prevent movement, the rollers release the card. As the card 25 is progressively placed in contact with the drum surface 28, the air cushion between the card 25 and the drum surface 28 is expelled and by the time the pinch rollers 24 and feed rollers 22 release the card 25, suflicient air film has been expelled by centrifugal forces on the card 25 to prevent unwanted slipping or skewing. Due to the speed imparted to the card 25 being equal to the speed of the drum surface 28, there is no relative movement between the two during insertion. This eliminates fiutter.

The drum 10 is rotated by its drive means 17 at such a speed that the centrifugal force of the card 25 being Iotated with the drum will hold it against the drum surface 28.

Experimentation has shown that with certain types of card a tangential velocity in excess of 150 inches per second is required to hold the card on the surface of the drum using a drum approximately 9 inches in diameter. It is understood that required tangential velocities will vary with the selection of the drum diameter and the type of document being transported. Satisfactory reading of magnetic cards has been experienced at tangential velocities of approximately 400 inches per second. The upper limits of the speed are believed to be limited only by the strength of the document and its capability of withstanding the acceleration forces during insertion.

Card feed rates in excess of 1,000 cards per minute can be achieved in a transport of this type if rcquirements dictate.

As the card revolves with the surface of the drum, it is carried by the revolving drum past the read head 48 where the data on the card is sensed and transmitted to the machine or system using that information. Where data may only be read one line at a time or one tier at a time as in a multi-tier card, repeated passage past the document read head 48 is required to retrieve all the data recorded on the card without the use of sophisticated storage and buffering devices. Therefore, it is often desirable to retain the card on the interior surface of the drum for a number of revolutions thereby passing the card 25 past the head 48 as many times as needed. In the event that an error is detected or proper data is not received, the card 25 may merely be rotated past the head 48 for a second reading.

Upon the completion of the reading phase, the electromagnet 44 is energized, thereby attracting the diverter plate 14 toward the electromagnet. As shown in lFIG. 4b, the diverter plate 14 is attracted by the electromagnet and the diverter fingers 38 are then pivoted into the channels 36 carried by the interior surface of the revolving drum 10. As the card approaches the diverter plate, which has been positioned as just described above, the card 25 then rides up onto the diverter plate as illustrated in FIG. 4b. The momentum of the card 25 carries the card onto the diverter plate 14, buckles the card 25 to conform roughly to the helical convolution of the diverter plate 14, and is thus guided onto the planar portion of the diverter guide 16. Any conventional sheet receiving mechanism, as pointed out above, can then be incorporated and combined with the planar portion of the diverter guide to receive those documents which have been read and removed from the drum 10.

If the document read head 48 is positioned intermediate the document insertion feed rolls 22 and the diverter plate 14 and only one pass by the document read head -48 is required per card, then the diverter plate 14 may be continually engaged with the interior surface of the drum 10 and the channels 36 carried thereby, to effect a continuous serial reading.

If the document must be re-read several times for any reason, the diverter plate 14 may be de-activated and allowed to clear the surface of the drum permitting the document to indefinitely revolve with the drum as illustrated in FIG. 411.

Since the interior portion of the drum 10 is merely a transport means and as such has no reading or timing function, the card 25 may be inserted at any point on the internal periphery of the drum 10 and there is no need to register either the leading or following edge of the document with any particular point on the interior surface of the drum.

An additional sensing means 54 may be mounted adjacent the interior periphery of the drum 10' such that the card 25 passes the sensing means 54 and thereby acts to retard the feeding of another document until such time as the preceding document has been removed from the interior of the drum. This prevents documents overlapping on the drum and causing reading errors.

The momentum of the card is sufficient to cause the card to be removed from the surface of the drum and guided by the diverter guide surface away from the drum transport.

As can be seen from the foregoing description of the Structure and explanation of its Operation, one can easily see that by combining a feed and insertion mechanism and a document removal and guding mechanism with a rotating drum adapted to carry a document by centrifugal force on its interior cylndrical surface accomplishes the objects of the invention set forth above by: providing an improvement over prior art document transport Systems; allowing a variable duration reading cycle in a document reader; simplifying the mechanical transport mechanism in a document reader; reducng the size of the document transport mechanism to only slightly more than the diameter of the revolving drum; and finally by obviating the need for accurate phase registration of the document with respect to the transport and read mechanisms and utilizing centrifugal force to overcome fiutter.

The invention is illustrated as a drum, a cornering feed mechanism, and a helical convolution acting as a document diverter and guide. It is recognized by one skilled in the art that any other conventional feed mechanism may be substituted which presents the card edgewise to the interior surface of the rotating drum such that it may be carried with the drum and then past reading stations. It is also recognized by those skilled in the art that an alternative removal means could be substituted for the helical convolution such as a Stripper and a cornering station thereby removing the document. Other variations may also be made in the Structure of the invention without departing from the spirit and Scope of the invention.

The invention is further described with a hinge connecting the document diverter plate and the diverter document guide. It is obvous that the document plate and guide could be of one piece and of such material and dimension as to permit it to be flexed into its two operative and inoperative positions thereby obviating the need for a hinge.

This document transport could also be incorporated into a sorter where a plurality of document diverters and document diverter guides were positioned at spaced locations around the periphery of part of the drum. By activating the selected diverter, the document would then be diverted into its proper stacker.

One sklled in the art also would recognize that the drum need not be closed on one end as is illustrated. If the drum is an open cylinder then the insertion and diverting apparatuses may work out of opposite ends of the cylinder. In such a configuration, the drum would then be peripherally driven and a support arrangement would then be necessary. However, since the drive mechanism is not a part of this invention, it is not shown in detail in the drawings.

While the invention has been particularly shown and described with reference to preferred and alternate embodiments thereof, it will be understood by those sklled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention.

What is claimed is:

1. A document transport system comprising:

a hollow cylindrical rotating drum;

document insertion means positioned partally interiorly of said drum;

document removal means positioned partially interiorly of said drum;

whereby a document may be nserted into, carried by,

and removed from the interior of said rotating drum.

2. A document transport system as in claim 1 wherein said drum has a plurality of parallel channels formed into the interior cylindrical surface of said drum, whereby portions of said document removal means may extend exteriorly of said cylindrical surface to divert said document from said drum.

3. A document transport system as in claim 1 wherein said document insertion means comprises document arresting means, and document cornering means whereby said document insertion means presents documents edgewise to said drum such that said documents are nserted on the interior cylindrical surface of said drum and carried thereon by centrifugal force.

4. A document transport system as in claim 2 wherein said removal means comprises a document diverter, said document diverter having a plurality of projections extending into said parallel channels, said document diverter projections selectively movable into and out of said channels whereby said removal means interrupts said document's circular movement and causes said document to move away from said interior cylindrical surface of said drum.

5. A document transport system as in claim 4 wherein said removal means comprises a document guiding means in the form of a partial helical convolution, said document diverter movably attached thereto, whereby said document is guided after removal from said drum.

6. A document transport system as in claim 4 wherein said removal means is further comprised of an actuation means operably connected to said document diverter for selectively moving said document diverter.

7. The method of serially transporting documents comprising the steps of:

cornering a document within a hollow rotating cylindrical drum;

propelling said document toward the interior cylindrical surface of said drum;

transporting said document on said drum surface; and

helically deforming said document progressively to remove said document from said drum surface and direct said card outwardly from said drum.

8. The method of serially transporting documents as in claim 7 wherein the additional step of accelerating said document until the relative velocity of said document with respect to the velocity of the interior of said drum is approximately Zero, is accomplished simultaneously with the step of propelling said document, whereby all relative movement between said drum and said document is eliminated.

References Cited UNITED STATES PATENTS 3,l37,499 6/1964 Maidment 271-64X 3,343,149 9/1967 Bleiman 340 l74.1 3,4l0,992 11/1968 Wiesler et al. 235 6l.11

JOSEPH WEGBREIT, Primary Examiner B. H. STONER, JR., Assistant Examiner U.S. Cl. X.R. 271-64, 

